Can Obama avoid mission creep in Iraq?

Iraqi army and volunteer fighters prepare in the Sedull Udeyim region of Iraq on Sunday, March 1, before an operation against ISIS in Tikrit, Iraq.

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Displaced Assyrian women who fled their homes due to ISIS attacks pray at the Ibrahim Al-Khalil Melkite Greek Catholic Church on the outskirts of Damascus, Syria, on March 1. ISIS militants recently abducted at least 220 Assyrians in Syria.

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Members of the Iraqi security forces leave Samarra, Iraq, north of Baghdad, on Saturday, February 28, to drive toward Tikrit to launch an assault against ISIS.

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A woman looks at her destroyed home after returning to the village of Al-Mansuriya, Iraq, on Saturday, February 14.

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Safi al-Kasasbeh, right, receives condolences from tribal leaders at his home village near Karak, Jordan, on Wednesday, February 4. Al-Kasasbeh's son, Jordanian pilot Moath al-Kasasbeh, was burned alive in a video that was recently released by ISIS militants. Jordan is one of a handful of Middle Eastern nations taking part in the U.S.-led military coalition against ISIS.

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A Kurdish marksman looks over a destroyed area of Kobani, Syria, on Friday, January 30, after the city had been liberated from the ISIS militant group. Kobani, also known as Ayn al-Arab, had been under assault by ISIS since mid-September.

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Smoke billows in Kirkuk, Iraq, as Kurdish Peshmerga fighters take position against ISIS militants on January 30. The aim of ISIS is to create an Islamic state across Sunni areas of Iraq and in Syria.

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Kurdish people celebrate in Suruc, Turkey, near the Turkish-Syrian border, after ISIS militants were expelled from Kobani on Tuesday, January 27.

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Collapsed buildings are seen in Kobani on January 27 after Kurdish forces took control of the town from ISIS.

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Junko Ishido, mother of Japanese journalist Kenji Goto, reacts during a news conference in Tokyo on Friday, January 23. ISIS would later kill Goto and another Japanese hostage, Haruna Yukawa.

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ISIS militants are seen through a rifle's scope during clashes with Peshmerga fighters in Mosul, Iraq, on Wednesday, January 21.

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An elderly Yazidi man arrives in Kirkuk after being released by ISIS on Saturday, January 17. The militant group released about 200 Yazidis who were held captive for five months in Iraq. Almost all of the freed prisoners were in poor health and bore signs of abuse and neglect, Kurdish officials said.

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Smoke billows behind an ISIS sign during an Iraqi military operation to regain control of the town of Sadiyah, about 95 kilometers (60 miles) north of Baghdad, on Tuesday, November 25.

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Fighters from the Free Syrian Army and the Kurdish People's Protection Units join forces to fight ISIS in Kobani on Wednesday, November 19.

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A picture taken from Turkey shows smoke rising after ISIS militants fired mortar shells toward an area controlled by Syrian Kurdish fighters near Kobani on Monday, November 3.

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Iraqi special forces search a house in Jurf al-Sakhar, Iraq, on Thursday, October 30, after retaking the area from ISIS.

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ISIS militants stand near the site of an airstrike near the Turkey-Syria border on Thursday, October 23. The United States and several Arab nations have been bombing ISIS targets in Syria to take out the militant group's ability to command, train and resupply its fighters.

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Kurdish fighters walk to positions as they combat ISIS forces in Kobani on Sunday, October 19.

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A U.S. Air Force plane flies above Kobani on Saturday, October 18.

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Heavy smoke rises in Kobani following an airstrike by the U.S.-led coalition on October 18.

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Cundi Minaz, a female Kurdish fighter, is buried in a cemetery in the southeastern Turkish town of Suruc on Tuesday, October 14. Minaz was reportedly killed during clashes with ISIS militants in nearby Kobani.

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Turkish police officers secure a basketball stadium in Suruc on October 14. Some Syrian Kurds were held there after crossing from Syria into Turkey. Tens of thousands of people fled Kobani to escape ISIS.

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Kiymet Ergun, a Syrian Kurd, celebrates in Mursitpinar, Turkey, after an airstrike by the U.S.-led coalition in Kobani on Monday, October 13.

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Alleged ISIS militants stand next to an ISIS flag atop a hill in Kobani on Monday, October 6.

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In this photo released by the U.S. Air Force on Saturday, October 4, a U.S. Navy jet is refueled in Iraqi airspace after conducting an airstrike against ISIS militants.

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A Kurdish Peshmerga soldier who was wounded in a battle with ISIS is wheeled to the Zakho Emergency Hospital in Duhuk, Iraq, on Tuesday, September 30.

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Syrian Kurds wait near a border crossing in Suruc as they wait to return to their homes in Kobani on Sunday, September 28.

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Tomahawk missiles, intended for ISIS targets in Syria, fly above the Persian Gulf after being fired by the USS Philippine Sea in this image released by the U.S. Navy on Tuesday, September 23.

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Turkish Kurds clash with Turkish security forces during a protest near Suruc on Monday, September 22. According to Time magazine, the protests were over Turkey's temporary decision to close the border with Syria.

Kurdish Peshmerga fighters fire at ISIS militant positions from their position on the top of Mount Zardak, east of Mosul, Iraq, on Tuesday, September 9.

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Iraqi volunteer fighters celebrate breaking the Amerli siege on Monday, September 1. ISIS militants had surrounded Amerli, 70 miles north of Baquba, Iraq, since mid-June.

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Kurdish Peshmerga forces stand guard at their position in the Omar Khaled village west of Mosul on Sunday, August 24.

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Kurdish Peshmergas fight to regain control of the town of Celavle, in Iraq's Diyala province, on August 24.

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Peshmerga fighters stand guard at Mosul Dam in northern Iraq on Thursday, August 21. With the help of U.S. military airstrikes, Kurdish and Iraqi forces retook the dam from ISIS militants on August 18. A breach of the dam would have been catastrophic for millions of Iraqis who live downstream from it.

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Displaced Iraqis receive clothes from a charity at a refugee camp near Feeshkhabour, Iraq, on Tuesday, August 19.

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Peshmerga fighters inspect the remains of a car that reportedly belonged to ISIS militants and was targeted by a U.S. airstrike in the village of Baqufa, north of Mosul, on August 18.

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Kurdish Peshmerga fighters fire at ISIS in Khazair, Iraq, on Thursday, August 14.

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Aziza Hamid, a 15-year-old Iraqi girl, cries for her father while she and some other Yazidi people are flown to safety Monday, August 11, after a dramatic rescue operation at Iraq's Mount Sinjar. A CNN crew was on the flight, which took diapers, milk, water and food to the site where as many as 70,000 people were trapped by ISIS. But only a few of them were able to fly back on the helicopter with the Iraqi Air Force and Kurdish Peshmerga fighters.

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Thousands of Yazidis are escorted to safety by Kurdish Peshmerga forces and a People's Protection Unit in Mosul on Saturday, August 9.

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Thousands of Yazidi and Christian people flee Mosul on Wednesday, August 6, after the latest wave of ISIS advances.

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A Baiji oil refinery burns after an alleged ISIS attack in northern Selahaddin, Iraq, on Thursday, July 31.

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A Syrian rebel fighter lies on a stretcher at a makeshift hospital in Douma, Syria, on Wednesday, July 9. He was reportedly injured while fighting ISIS militants.

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Peshmerga fighters clean their weapons at a base in Tuz Khormato on June 25.

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New army recruits gather in Najaf, Iraq, on Wednesday, June 18, following a call for Iraqis to take up arms against Islamic militant fighters.

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Kurdish Peshmerga forces, along with Iraqi special forces, deploy their troops and armored vehicles outside of Kirkuk, Iraq, on June 12.

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Children stand next to a burnt vehicle during clashes between Iraqi security forces and ISIS militants in Mosul on Tuesday, June 10.

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Civilians from Mosul escape to a refugee camp near Irbil, Iraq, on June 10.

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Story highlights

President Obama plans to send 300 military advisers to Iraq to stabilize conflict

Julian Zelizer: History shows us that mission creep is difficult to avoid

He says many operations - in Korea, Vietnam, Somalia - start small but end big

Zelizer: Obama could find himself forced to send more troops than he expected

(CNN)President Obama is about to send up to 300 military advisers to Iraq in an attempt to stabilize a situation that is rapidly disintegrating. Obama had hoped that the end of the Iraq war would be a key accomplishment of his administration. But just as he thought it was safe to get out, the President is finding himself drawn back, as violence has been spreading throughout Iraq.

Understanding that American patience for another war is limited, President Obama promises this mission will be contained.

But mission creep is difficult to avoid. The history of military involvement shows that many operations that start small end big. While the United States initially entered Korea to try to get the North Koreans out of South Korea after an invasion, President Harry Truman found himself presiding over a full-scale military mobilization that lasted three years, cost over 30,000 lives and helped bring down his administration.

Julian Zelizer

Vietnam started small, with military advisers under Presidents Dwight Eisenhower and John F. Kennedy. Even when President Lyndon Johnson requested from Congress the Gulf of Tonkin Resolution that granted him broad authority to use military force, he didn't imagine how big the conflict would become, resulting in the death of nearly 60,000 U.S. soldiers and dramatically undermining America's role in the world.

Examples of mission creep continued. George H.W. Bush had 30,000 troops enter into a peacekeeping mission in Somalia. The mission didn't go so well. As a result of an attack on U.N. forces by a warlord in the country, the operation expanded and President Clinton found himself ordering more expansive operations.

Although George H.W. Bush was determined to stick to his goal of kicking Saddam Hussein out of Kuwait in 1990 and 1991, once troops were in the region, the United States became committed to ongoing engagement with Hussein as he flouted U.N. resolutions. In Afghanistan and Iraq after 9/11, the United States vastly broadened the scale and scope of its operations as challenges of post-regime reconstruction proved immense.

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Why does it prove so difficult to contain operations? Why is mission creep so common? Most importantly, war inherently involves many moving parts, most of which are not under the control of the commander in chief.

Often, as was the case with South Vietnam in the 1960s, allies prove difficult to rely on and cause problems of their own, while opponents frequently are capable of causing far more trouble than expected, even when they have fewer resources than the United States.

Although a mission might seem small at first, the logic of war creates new dangers for advisers or soldiers in the field and makes it very difficult to avoid pouring more resources into a problem.

Domestic politics also matter. Very often the political pressures to escalate intensify once a president has committed forces to a region, particularly in the early years of a conflict. Both parties, as was the case with the Cold War and in the aftermath of 9/11, vie to be the party that will be tougher against the nation's adversary. Neither party wants to look weak, to be the party, as Republicans said of Democrats after 1949, that lost China to communism.

Finally, in this day and age, many of the missions that involve U.S. troops are not clear-cut or well defined. It is unclear what victory even looks like anymore. During the war against terrorism, the United States has found itself drawn into operations where it is trying to create stable government structures that will not house terrorist networks or work on a continuous basis in countries to fight against fundamentalist forces. None of this lends itself to a quick end or to limited involvement.

President Obama might get lucky and find that the advisers he sent to do the job get the job done. But history shows that mission creep can also happen quite quickly, and the President could easily find himself forced to send more troops than he expected into the quagmire of Iraq.